Manufacture of artificial wood



moistened mass is Patented an. i 12, 1926.

UNITED STATES 1,569,272 PATENT OFFICE- ADOLF F6BSTEB, 0F KULLEBUNI), NEAR CHRISTIANIA, NORWAY.

MANUFACTURE OF ARTIFICIAL WOOD.

No Drawing.

To all whom it may concern:

Be it known that I, Anonr Fons'rnn, of Kullebund, near Christiania, Norway, have invented certain new and useful Improvements in the Manufacture of Artificial An important feature of the present process as compared with hitherto known processesv of this type consists therein that the glue is incorporated into the other constituents of the composition by means of moistening with a quite dilute solution of glue, which before application has been intimately mixed with a solution of a tanning or coagulating agent.

In the manufacture of artificial wood in accordance with the present invention one may for example proceed as follows:

parts by weight of saw dust and 10 parts by weight of chalk are thoroughly mixed so that the individual particles of saw dust are entirely enclosed in chalk.

This mixture of saw dust and chalk is moistened with a solution produced'in the following manner:

7 parts by weight of ordinary glue (j-oiners glue) are dissolved in 9095 parts by weight of water and when dissolution has been effected 5-10 parts by weight of acetic acid (according to the qualityof the glue) is added. This solution is thoroughly mixed with an aqueous solution 'of potassium bichroinate in a quantity of from 23 per centbf the weight of the dry glue.

To the first mentioned mixture of saw dust and chalk is now added so much of the chromate-glue solution (suitably about 35- 45 kilogrammes) that the mass becomes well moistened throughout but not more. The worked thoroughly through preferably in full daylight and is thereupon brought into m'oulds (preferably with smooth, surfaces), which are suitably constructed of iron and is subjected for some time (for example a couple of hours) to a very high pressure. The shaped objects are thereupon removed from the moulds and Application filed October 17, 1923. Serial No. 669,186.

' dried in the air. In the described example the dry product for each kilogram of sawdust-chalk mixture will not contain more than about-0.03 kilogrammes of glue.

The completely dried product can be worked as natural wood with saw, plane,

drill and other wood-working tools. The

material can also be glued (joined),' coloured, painted and fastened by nails or screws.

Instead of chalk other mineral fillers of a low degree-0f hardness such as soap-stone, talcum may also-be employed. The addition of acetic acid to the composition is not ab- I solutely necessary but will in most instances produce the best results. The otassium bichromate can wholly or in part e substituted for by other substances, which have a tanning or coagulating efi'ect upon gelatine, but it has been found, that the best results are obtained by the use of a chromate or chromic acid as a hardener.

. It is of great importance, that a dilute solution of glue is used so that the percentage of glue, which is incorporated into the composition by the moistening operation,

is quite small.

Products produced according to this invention can be exposed to atmospheric infiuences without warping and without shrinking or cracking. It is only a little heavier than natural wood and floats on water. The roduct is insoluble in water and burns on .y when subjected to very high temperatures-high glow heatand does not rot owing to thefcontained chemicals. The moist composition can be pressed directly upon veneer by placing the veneer in the bottom of the mould. The veneer cannot afterwards'be loosened from the dry mass. Veneered plates produced in this manner are not subjected to the drawbacks frequently connected with natural wood which gonsist in warping and cracking of the wood ase.

The manufacturing costs of the artificial wood product is low. It is hard and has a great resistance against wear, and it can therefore with great advantage be used in steps of staircases, and in slabs of suitable si ze for Wainscot, for floors etc. Reinforced with iron the material may be used to produce window frames and other objects.

.Further this artificial wood can be used in the'manufacture of frniture and many other obj ects- Claims. 1. Method of manufacturing artificlal wood comprising the stepsof moislcning a.

mixture containing saw dust and a soft mineralfiller with a dilute solution of chro-- mate-glue in .which the percentage of glue is considerably less than 10 per cent thoroughly working the moistened mixture, moulding the resulting mass under a high pressure, maintaining the pressure for a considerable time and subjecting the moulded articles to drying.

2. Method of producing artificial wood ADOLF FURSTER. 

